Effect of an Immersive Preoperative Virtual Reality Experience on Patient Reported Outcomes: A Randomized Controlled Trial.

OBJECTIVE: To investigate the effect of exposure to a virtual reality (VR) environment preoperatively on patient-reported outcomes for surgical operations. BACKGROUND: There is a scarcity of well-developed quality improvement initiatives targeting patient satisfaction. METHODS: We performed a randomized controlled trial of patients undergoing cranial and spinal operations in a tertiary referral center. Patients underwent a 1:1 randomization to an immersive preoperative VR experience or standard preoperative experience stratified on type of operation. The primary outcome measures were the Evaluation du Vecu de l'Anesthesie Generale (EVAN-G) score and the Amsterdam Preoperative Anxiety and Information (APAIS) score, as markers of the patient's experience during the surgical encounter. RESULTS: During the study period, a total of 127 patients (mean age 55.3 years, 41.9% females) underwent randomization. The average EVAN-G score was 84.3 (standard deviation, SD, 6.4) after VR, and 64.3 (SD, 11.7) after standard preoperative experience (difference, 20.0; 95% confidence interval, CI, 16.6-23.3). Exposure to an immersive VR experience also led to higher APAIS score (difference, 29.9; 95% CI, 24.5-35.2). In addition, VR led to lower preoperative VAS stress score (difference, -41.7; 95% CI, -33.1 to -50.2), and higher preoperative VAS preparedness (difference, 32.4; 95% CI, 24.9-39.8), and VAS satisfaction (difference, 33.2; 95% CI, 25.4-41.0) scores. No association was identified with VAS stress score (difference, -1.6; 95% CI, -13.4 to 10.2). CONCLUSIONS: In a randomized controlled trial, we demonstrated that patients exposed to preoperative VR had increased satisfaction during the surgical encounter. Harnessing the power of this technology, hospitals can create an immersive environment that minimizes stress, and enhances the perioperative experience.

A Pineal Parenchymal Tumor of Intermediate Differentiation in an Octogenarian Contains a Rare KBTBD4 Insertion.

Pineal parenchymal tumors are rare central nervous system tumors that pose diagnostic challenges for surgical pathologists. Due to their paucity, their clinicopathologic features are still being defined. We report an 86-year-old woman with a remote history of breast lobular carcinoma who presented with a 2-month neurologic history that included gait instability, blurry vision, and headaches. Magnetic resonance imaging revealed a lobular, heterogeneously enhancing pineal region mass compressing the aqueduct of Sylvius. A biopsy performed concomitant with endoscopic third ventriculostomy consisted of small sheets of cells with eosinophilic to clear cytoplasm, multipolar processes, and ovoid nuclei with stippled chromatin. Whole exome sequencing revealed a small in-frame insertion (duplication) in exon 4 of KBTBD4 (c.931_939dup, p.P311_R313dup/ p.R313_M314insPRR), which has very recently been reported in 2 pineal parenchymal tumors of intermediate differentiation (PPTID). Additionally, variants of uncertain significance in CEBPA (c.863G > C, p.R288P) and MYC (c.655T > C, p.S219P) were identified. Although PPTID is considered a disease of young adulthood, review of 2 institutional cohorts of patients with pineal region tumors revealed that 25% of individuals with PPTID were over 65 years of age. In conclusion, PPTID should be considered in the differential diagnosis of pineal region tumors in older adults.

Racial Disparities in Outcomes After Spine Surgery: A Systematic Review and Meta-Analysis.

OBJECTIVE: Racial disparities are a major issue in health care but the overall extent of the issue in spinal surgery outcomes is unclear. We conducted a systematic review/meta-analysis of disparities in outcomes among patients belonging to different racial groups who had undergone surgery for degenerative spine disease. METHODS: We searched Ovid MEDLINE, Scopus, Cochrane Review Database, and ClinicalTrials.gov from inception to January 20, 2021 for relevant articles assessing outcomes after spine surgery stratified by race. We included studies that compared outcomes after spine surgery for degenerative disease among different racial groups. RESULTS: We found 30 studies that met our inclusion criteria (28 articles and 2 published abstracts). We included data from 20 cohort studies in our meta-analysis (3,501,830 patients), which were assessed to have a high risk of observation/selection bias. Black patients had a 55% higher risk of dying after spine surgery compared with white patients (relative risk [RR], 1.55, 95% confidence interval [CI], 1.28-1.87; I2 = 70%). Similarly, black patients had a longer length of stay (mean difference, 0.93 days; 95% CI, 0.75-1.10; I2 = 73%), and higher risk of nonhome discharge (RR, 1.63; 95% CI, 1.47-1.81; I2 = 89%), and 30-day readmission (RR, 1.45; 95% CI, 1.03-2.04; I2 = 96%). No significant difference was noted in the pooled analyses for complication or reoperation rates. CONCLUSIONS: Black patients have a significantly higher risk of unfavorable outcomes after spine surgery compared with white patients. Further work in understanding the reasons for these disparities will help develop strategies to narrow the gap among the racial groups.

Association between interhospital transfer and increased in-hospital mortality in patients with spinal epidural abscesses.

BACKGROUND CONTEXT: Spinal epidural abscess (SEA) is an uncommon yet serious infection, associated with significant morbidity and mortality. Patients diagnosed with SEA often require surgical interventions or critical care services that are not available at community hospitals and are therefore transferred to tertiary care centers. Little is known about the effects of interhospital transfer on acute outcomes for patients with SEA. PURPOSE: To study the effects of interhospital transfer on acute outcomes for patients with SEA. STUDY DESIGN: Cross sectional analysis using the 2009 to 2017 National Inpatient Sample (NIS). PATIENT SAMPLE: Using the 2009 to 2017 NIS, we identified cases of SEA using ICD, Ninth, or Tenth Revision diagnosis codes 324.1 & G06.1. OUTCOME MEASURES: Our primary endpoint was in hospital mortality. METHODS: The association between interhospital transfer and inpatient mortality was assessed using multivariable logistic regression to adjust for potential covariates. Patient and hospital factors associated with interhospital transfer were assessed in a secondary analysis. RESULTS: A total of 21.5% of patient with SEA were treated after transfer from another hospital. After adjusting for covariates, those who presented after transfer had higher odds of death during hospitalization (OR: 1.51, 95% CI 1.27-1.78, p<.001). Transferred patients were significantly more likely to live in rural communities (11.4 % vs. 5.3 % for nontransferred patients). CONCLUSIONS: Interhospital transfer, which occurred more frequently in patients from rural hospitals, was associated with death even after controlling for disease severity. Addressing healthcare delivery disparities across the US, including across the rural-urban spectrum, will require better understanding of the observed increased mortality of interhospital transfer as a preventable source of in-hospital mortality for SEA.

A lesser scaup (Aythya affinis) naturally infected with Eurasian 2.3.4.4 highly pathogenic H5N1 avian influenza virus: Movement ecology and host factors.

Despite the recognized role of wild waterfowl in the potential dispersal and transmission of highly pathogenic avian influenza (HPAI) virus, little is known about how infection affects these birds. This lack of information limits our ability to estimate viral spread in the event of an HPAI outbreak, thereby limiting our abilities to estimate and communicate risk. Here, we present telemetry data from a wild Lesser Scaup (Aythya affinis), captured during a separate ecology study in the Chesapeake Bay, Maryland. This bird tested positive for infection with clade 2.3.4.4 HPAI virus of the A/goose/Guangdong/1/1996 (Gs/GD) H5N1 lineage (results received post-release) during the 2021-2022 ongoing outbreaks in North America. While the infected bird was somewhat lighter than other adult males surgically implanted with transmitters (790 g, x̅ = 868 g, n = 11), it showed no clinical signs of infection at capture, during surgery, nor upon release. The bird died 3 days later-pathology undetermined as the specimen was not able to be recovered. Analysis of movement data within the 3-day window showed that the infected individual's maximum and average hourly movements (3894.3 and 428.8 m, respectively) were noticeably lower than noninfected conspecifics tagged and released the same day (x̅ = 21,594.5 and 1097.9 m, respectively; n = 4). We identified four instances where the infected bird had close contact (fixes located within 25 m and 15 min) with another marked bird during this time. Collectively, these data suggest that the HPAI-positive bird observed in this study may have been shedding virus for some period prior to death, with opportunities for direct bird-to-bird or environmental transmission. Although limited by low sample size and proximity to the time of tagging, we hope that these data will provide useful information as managers continue to respond to this ongoing outbreak event.

Sensitizing brain metastases to stereotactic radiosurgery using hyperbaric oxygen: A proof-of-principle study.

PURPOSE: Increased oxygen levels may enhance the radiosensitivity of brain metastases treated with stereotactic radiosurgery (SRS). This project administered hyperbaric oxygen (HBO) prior to SRS to assess feasibility, safety, and response. METHODS: 38 patients were studied, 19 with 25 brain metastases treated with HBO prior to SRS, and 19 historical controls with 27 metastases, matched for histology, GPA, resection status, and lesion size. Outcomes included time from HBO to SRS, quality-of-life (QOL) measures, local control, distant (brain) metastases, radionecrosis, and overall survival. RESULTS: The average time from HBO chamber to SRS beam-on was 8.3 ± 1.7 minutes. Solicited adverse events (AEs) were comparable between HBO and control patients; no grade III or IV serious AEs were observed. Radionecrosis-free survival (RNFS), radionecrosis-free survival before whole-brain radiation therapy (WBRT) (RNBWFS), local recurrence-free survival before WBRT (LRBWFS), distant recurrence-free survival before WBRT (DRBWFS), and overall survival (OS) were not significantly different for HBO patients and controls on Kaplan-Meier analysis, though at 1-year estimated survival rates trended in favor of SRS + HBO: RNFS - 83% vs 60%; RNBWFS - 78% vs 60%; LRBWFS - 95% vs 78%; DRBWFS - 61% vs 57%; and OS - 73% vs 56%. Multivariate Cox models indicated no significant association between HBO treatment and hazards of RN, local or distant recurrence, or mortality; however, these did show statistically significant associations (p < 0.05) for: local recurrence with higher volume, radionecrosis with tumor resection, overall survival with resection, and overall survival with higher GPA. CONCLUSION: Addition of HBO to SRS for brain metastases is feasible without evident decrement in radiation necrosis and other clinical outcomes.

Improving the Usability of 5-Aminolevulinic Acid Fluorescence-Guided Surgery by Adding an Optimized Secondary Light Source.

BACKGROUND: Tumors that take up and metabolize 5-aminolevulinic acid emit bright pink fluorescence when illuminated with blue light, aiding surgeons in identifying the margin of resection. The adoption of this method is hindered by the blue light illumination, which is too dim to safely operate under and therefore necessitates switching back and forth from white-light mode. The aim of this study was to examine the addition of an optimized secondary illuminant adapter to improve usability of blue-light mode without degrading tumor contrast. METHODS: Color science methods were used to evaluate the color of the secondary illuminant and its impact on color rendering index as well as the tumor-to-background color contrast in data collected from 7 patients with high-grade gliomas (World Health Organization grade III and IV). A secondary illuminant adapter was built to provide 475-600 nm light the intensity of which can be controlled by the surgeon and was evaluated in 2 additional patients. RESULTS: Secondary illuminant color had opposing effects on color rendering index and tumor-to-background color contrast; providing surgeon control of intensity allows this trade-off to be balanced in real time. Demonstration in 2 high-grade glioma cases confirms this, showing that additional visibility adds value when intensity can be controlled by the surgeon. CONCLUSIONS: Addition of a secondary illuminant may mitigate surgeon complaints that the operative field is too dark under the blue light illumination required for 5-aminolevulinic acid fluorescence guidance by providing improved color rendering index without completely sacrificing tumor-to-background color contrast.

False Localization of Ruptured Intracranial Dermoid Secondary to Subarachnoid Spread of Cyst Contents.

A 34-year-old right-handed female presented to the emergency department with a worsening headache, neck stiffness, intermittent abnormal sensation, and right arm weakness. Shortly after arrival, she had a generalized tonic-clonic seizure. A noncontrast head computed tomography scan revealed a right-sided, low-attenuating, lobulated mass ipsilateral to her arm symptoms. Magnetic resonance imaging revealed an abnormal signal throughout the subarachnoid space and increased fluid-attenuated inversion recovery sequence signal contralateral to the mass. This presentation suggested a false localization sign of sensory and motor disturbance ipsilateral to the mass likely caused by cyst rupture and sebum spread contralateral, causing cortical irritation (evidenced by increased fluid-attenuated inversion recovery sequence signal). During mass resection, sebum was visible throughout the subarachnoid space. The patient had an uneventful recovery from surgery and has been seizure free since the resection with steady improvement of symptoms. This case highlights the importance of avoiding cyst rupture of dermoid cysts.

Prehospital Predictors of Emergent Intervention After Helicopter Transfer for Spontaneous Intraparenchymal Hemorrhage.

OBJECTIVE: Helicopter transport may shorten transportation times for emergent neurosurgical intervention. The usefulness of helicopter transport after spontaneous intraparenchymal hemorrhage is not well studied. This study seeks to clarify factors that are associated with urgent surgical intervention in patients with spontaneous intracerebral hemorrhage following helicopter transport. METHODS: Records were reviewed for patients with spontaneous intraparenchymal hemorrhage transported by helicopter to Dartmouth-Hitchcock Medical Center between January 2008 and December 2011. Records were evaluated for factors associated with emergent tertiary-level care intervention during the first 24 hours of admission. RESULTS: A total of 107 patients met inclusion criteria, with a mean age of 67.2 years. At presentation, 79 (75.24%) were hypertensive, 22 (21.57%) had an increased international normalized ratio, and 47 (45.19%) were intubated. Thirty-three patients (30.8%) underwent 1 or more neurosurgical interventions within 24 hours of arrival, with an additional 6 (5.6%) patients undergoing neurosurgical intervention after 24 hours after admission. On univariate analysis, age, Glasgow Coma Scale (GCS) score, and clot volume were significant predictors of neurosurgical intervention within 24 hours of interfacility helicopter transport. A lobar clot, presence of intraventricular hemorrhage, and presence of >1 cm of midline shift were also associated with neurosurgical intervention within 24 hours. On multivariate analysis, younger age, GCS score of 3-8, and lobar hemorrhage were independent predictors of neurosurgical intervention within 24 hours. CONCLUSIONS: Two thirds of patients did not undergo any surgical intervention during the first 24 hours of admission after interfacility helicopter transfer. Factors associated with urgent neurosurgical intervention included younger age, low GCS score, and presence of lobar hemorrhage.

A Cohort Study of the Natural History of Odontoid Pseudoarthrosis Managed Nonoperatively in Elderly Patients.

OBJECTIVE: Although the primary goal of treatment of type II odontoid fracture is bony union, some advocate continued nonsurgical management of minimally symptomatic older patients who have fibrous union or minimal fracture motion. The risk of this strategy is unknown. We reviewed our long-term outcomes after dens nonunion to define the natural history of Type II odontoid fractures in elderly patients managed nonoperatively. METHODS: A retrospective chart review of 50 consecutive adults aged 65 or older with Type II odontoid fracture initially managed nonsurgically from 1998 to 2012 at a single tertiary care institution was conducted. Particular attention was paid to patients who had orthosis removal despite absent bony fusion. Patients were contacted prospectively by telephone and followed until death, surgical intervention, or last known contact. RESULTS: Fifty patients initially were managed nonsurgically; of these, 21 (42.0%) proceeded to bony fusion, 3 (6%) underwent delayed surgery for persistent instability, and 26 (52%) had orthosis removal despite the lack of solid arthrodesis on imaging. The last group had a median follow-up of 25 months (range 4-158 months), with 20 of 26 (76.9%) followed until death. Of these patients, 1 patient developed progressive quadriplegia and dysphagia 11 months after initial injury. Compared with patients with spontaneous union, patients with nonunion had shorter life expectancy, despite no significant differences between the groups with respect to age, sex, injury mechanism, radiographic variables, or follow-up duration. CONCLUSIONS: Orthosis removal despite fracture nonunion may be reasonable in elderly patients with Type II dens fractures.

Long-term response of pituitary carcinoma to temozolomide. Report of two cases.

Pituitary carcinoma is a rare tumor characterized by poor responsiveness to therapy, leading to early death. Reported responses to standard chemotherapy have only been anecdotal, with no single agent or combination demonstrating consistent efficacy in the treatment of patients with this disease. The authors report rare examples of a persistent response to cytotoxic chemotherapy in two patients with pituitary carcinoma. One patient was a 38-year-old man with visual field loss caused by a luteinizing hormone-secreting pituitary carcinoma that had recurred despite multiple surgeries and radiation therapy. Intradural metastases to the spine that had failed to respond to radiation therapy were pathologically confirmed. The second patient was a 26-year-old man with hyperprolactinemia from a prolactin-secreting pituitary tumor. Spine magnetic resonance images obtained to search for causes of neck pain showed a vertebral tumor, which was later confirmed through pathological analysis to be a metastatic pituitary carcinoma. His disease progressed despite radiation therapy, high-dose bromocriptine, and chemotherapy. Both patients were treated monthly with temozolomide, which was administered orally on the first 5 days of a 28-day cycle. The patient in the first case underwent all 12 treatment cycles without serious side effects, and his visual field deficits improved. The patient in the second case had undergone only 10 cycles when the drug was stopped because of his severe fatigue. Nonetheless, his pain disappeared and his serum prolactin concentration decreased. Both patients continue to have partial responses and have been employed full-time for more than 1 year after discontinuing temozolomide therapy. These two examples demonstrate that temozolomide may be effective in treating pituitary carcinomas and thus should be considered in the treatment algorithm for these difficult cases.

Operative Duration and Risk of Surgical Site Infection in Neurosurgery.

BACKGROUND: The association of surgical duration with the risk of surgical site infection (SSI) has not been quantified in neurosurgery. We investigated the association of operative duration in neurosurgical procedures with the incidence of SSI. METHODS: We performed a retrospective cohort study involving patients who underwent neurosurgical procedures from 2005 to 2012 and were registered in the American College of Surgeons National Quality Improvement Project registry. To control for confounding, we used multivariable regression models and propensity score conditioning. RESULTS: During the study period there were 94,744 patients who underwent a neurosurgical procedure and met the inclusion criteria. Of these patients, 4.1% developed a postoperative SSI within 30 days. Multivariable logistic regression showed an association between longer operative duration with higher incidence of SSI (odds ratio [OR], 1.18; 95% confidence interval [CI], 1.16-1.20). Compared with procedures of moderate duration (third quintile, 40th-60th percentile), patients undergoing the longest procedures (>80th percentile) had higher odds (OR, 2.07; 95% CI, 1.86-2.31) of developing SSI. The shortest procedures (<20th percentile) were associated with decreased incidence of SSI (OR, 0.72; 95% CI, 0.61-0.83) compared with those of moderate duration. The same associations were present in propensity score adjusted models and models stratified by subgroups of cranial, spinal, peripheral nerve, and carotid procedures. CONCLUSIONS: In a cohort of patients from a national prospective surgical registry, longer operative duration was associated with increased incidence of SSI for neurosurgical procedures. These results can be used by neurosurgeons to inform operative management and to stratify patients with regard to SSI risk.

Nervus Intermedius Symptoms following Surgical or Radiation Therapy for Vestibular Schwannoma.

OBJECTIVES: This study compares the functional outcomes of nevus intermedius impairment following surgery, radiation, or observation for the treatment of vestibular schwannoma. STUDY DESIGN: Retrospective cohort study. SETTINGS: Tertiary care medical center. SUBJECTS AND METHODS: We retrospectively examined 141 charts of patients with a vestibular schwannoma seen in the Dartmouth-Hitchcock Acoustic Neuroma Clinic between 2012 and 2014. Seventy-one patients underwent intervention (including radiation) as their primary treatment, and 70 were treated with observation. As part of routine care, patients were interviewed at clinic visits and with a questionnaire assessing nervus intermedius impairment. RESULTS: At presentation, 25 patients (19%) reported nervus intermedius impairment. Most common disturbances were xerophthalmia (dry eyes, 13%) and dysgeusia (taste alteration, 7.6%). Postintervention, 35 patients (53%) had ≥1 symptoms of nervus intermedius dysfunction, which is increased in comparison with patients in the observation group (17 patients, 26.5%, P < .05). Twelve intervention patients had symptoms resolve postoperatively, making no long-term difference between the observation and intervention groups (P = .20). Motor function of the facial nerve postoperatively is correlated with nervus intermedius symptoms. Surgical approaches were compared with radiation therapy, and no significant difference in nervus intermedius outcomes was found. CONCLUSION: This study demonstrates the clinical importance of monitoring nervus intermedius symptoms, since a high percentage of all patients undergoing intervention will be symptomatic during management. Patients with motor dysfunction are at a higher risk of developing nervus intermedius sequelae and need close follow-up. Although impairment is common, many symptoms will improve over time with no long-term difference between intervention patients and those under observation.

Kinematics and dynamics of the East Pacific Rise linked to a stable, deep-mantle upwelling.

Earth's tectonic plates are generally considered to be driven largely by negative buoyancy associated with subduction of oceanic lithosphere. In this context, mid-ocean ridges (MORs) are passive plate boundaries whose divergence accommodates flow driven by subduction of oceanic slabs at trenches. We show that over the past 80 million years (My), the East Pacific Rise (EPR), Earth's dominant MOR, has been characterized by limited ridge-perpendicular migration and persistent, asymmetric ridge accretion that are anomalous relative to other MORs. We reconstruct the subduction-related buoyancy fluxes of plates on either side of the EPR. The general expectation is that greater slab pull should correlate with faster plate motion and faster spreading at the EPR. Moreover, asymmetry in slab pull on either side of the EPR should correlate with either ridge migration or enhanced plate velocity in the direction of greater slab pull. Based on our analysis, none of the expected correlations are evident. This implies that other forces significantly contribute to EPR behavior. We explain these observations using mantle flow calculations based on globally integrated buoyancy distributions that require core-mantle boundary heat flux of up to 20 TW. The time-dependent mantle flow predictions yield a long-lived deep-seated upwelling that has its highest radial velocity under the EPR and is inferred to control its observed kinematics. The mantle-wide upwelling beneath the EPR drives horizontal components of asthenospheric flows beneath the plates that are similarly asymmetric but faster than the overlying surface plates, thereby contributing to plate motions through viscous tractions in the Pacific region.

MicroRNA and gene expression changes in unruptured human cerebral aneurysms.

OBJECTIVE The molecular mechanisms behind cerebral aneurysm formation and rupture remain poorly understood. In the past decade, microRNAs (miRNAs) have been shown to be key regulators in a host of biological processes. They are noncoding RNA molecules, approximately 21 nucleotides long, that posttranscriptionally inhibit mRNAs by attenuating protein translation and promoting mRNA degradation. The miRNA and mRNA interactions and expression levels in cerebral aneurysm tissue from human subjects were profiled. METHODS A prospective case-control study was performed on human subjects to characterize the differential expression of mRNA and miRNA in unruptured cerebral aneurysms in comparison with control tissue (healthy superficial temporal arteries [STA]). Ion Torrent was used for deep RNA sequencing. Affymetrix miRNA microarrays were used to analyze miRNA expression, whereas NanoString nCounter technology was used for validation of the identified targets. RESULTS Overall, 7 unruptured cerebral aneurysm and 10 STA specimens were collected. Several differentially expressed genes were identified in aneurysm tissue, with MMP-13 (fold change 7.21) and various collagen genes (COL1A1, COL5A1, COL5A2) being among the most upregulated. In addition, multiple miRNAs were significantly differentially expressed, with miR-21 (fold change 16.97) being the most upregulated, and miR-143-5p (fold change -11.14) being the most downregulated. From these, miR-21, miR-143, and miR-145 had several significantly anticorrelated target genes in the cohort that are associated with smooth muscle cell function, extracellular matrix remodeling, inflammation signaling, and lipid accumulation. All these processes are crucial to the pathophysiology of cerebral aneurysms. CONCLUSIONS This analysis identified differentially expressed genes and miRNAs in unruptured human cerebral aneurysms, suggesting the possibility of a role for miRNAs in aneurysm formation. Further investigation for their importance as therapeutic targets is needed.

Utility of Routine Outpatient Cervical Spine Imaging Following Anterior Cervical Corpectomy and Fusion.

BACKGROUND: Construct failure is an uncommon but well-recognized complication following anterior cervical corpectomy and fusion (ACCF). In order to screen for these complications, many centers routinely image patients at outpatient visits following surgery. There remains, however, little data on the utility of such imaging. METHODS: The electronic medical record of all patients undergoing anterior cervical corpectomy and fusion at Dartmouth-Hitchcock Medical Center between 2004 and 2009 were reviewed. All patients had routine cervical spine radiographs performed perioperatively. Follow-up visits up to two years postoperatively were analyzed.  RESULTS: Sixty-five patients (mean age 52.2) underwent surgery during the time period. Eighteen patients were female. Forty patients had surgery performed for spondylosis, 20 for trauma, three for tumor, and two for infection. Forty-three patients underwent one-level corpectomy, 20 underwent two-level corpectomy, and two underwent three-level corpectomy, using an allograft, autograft, or both. Sixty-two of the fusions were instrumented using a plate and 13 had posterior augmentation. Fifty-seven patients had follow-up with imaging at four to 12 weeks following surgery, 54 with plain radiographs, two with CT scans, and one with an MRI scan. Unexpected findings were noted in six cases. One of those patients, found to have asymptomatic recurrent kyphosis following a two-level corpectomy, had repeat surgery because of those findings. Only one further patient was found to have abnormal imaging up to two years, and this patient required no further intervention. CONCLUSIONS: Routine imaging after ACCF can demonstrate asymptomatic occurrences of clinically significant instrument failure. In 43 consecutive single-level ACCF however, routine imaging did not change management, even when an abnormality was discovered. This may suggest a limited role for routine imaging after ACCF in longer constructs involving multiple levels.

Spinal sealant system provides better intraoperative watertight closure than standard of care during spinal surgery: a prospective, multicenter, randomized controlled study.

STUDY DESIGN: Prospective, 3:1 randomized, single-blind, multicenter investigational study. OBJECTIVE: To assess the safety and efficacy of a low-swell spinal sealant when used as an adjunct to sutured dural repair compared with standard of care methods to obtain watertight dural closure in subjects undergoing spinal surgery. SUMMARY OF BACKGROUND DATA: Watertight dural closure is paramount in spinal surgery to avoid complications of cerebrospinal fluid leak. Prior reports have proven the efficacy of a synthetic, absorbable polyethylene glycol (PEG) hydrogel sealant in spinal surgery compared with standard of care. Given the potential concerns of swelling in spinal applications, the hydrogel was modified to a low-swell formulation. METHODS: The primary endpoint was success rate in obtaining intraoperative watertight dural closure in subjects receiving PEG hydrogel sealant versus a control group of subjects receiving any standard method designed to provide intraoperative watertight closure. Subjects were evaluated at discharge and at 30 and 90 days postprocedure for cerebrospinal fluid leaks, surgical site infections, and adverse events. RESULTS: Between May 2007 and May 2009, 98 subjects (74 PEG hydrogel spinal sealant, 24 control) were randomized at 14 clinical sites in the United States. Patients treated with the PEG hydrogel spinal sealant had a significantly higher rate of watertight closure than the control (98.6% vs. 79.2%, P = 0.003). No statistical differences were seen in postoperative cerebrospinal fluid, infection, and wound healing. No neurological deficits were seen attributable to the sealant. CONCLUSION: The low-swell PEG hydrogel spinal sealant evaluated in this study has been proven safe and effective for providing watertight closure when used as an adjunct to sutured closure of intentional durotomies during spinal surgery. PEG hydrogel sealants have again proved superior to other standard of care technologies for safe, efficacious dural closure. LEVEL OF EVIDENCE: 2.

Selection of patients for ambulatory lumbar discectomy: results from four US states.

BACKGROUND CONTEXT: There is a persistent trend for more outpatient lumbar discectomies in the United States. PURPOSE: To investigate the characteristics of the patients selected for ambulatory procedures. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Forty-seven thousand one hundred twenty-five patients who underwent outpatient and 102,592 patients undergoing inpatient lumbar discectomies and were were registered in the State Ambulatory Surgery Database (SASD) and State Inpatient Database (SID), respectively, for New York, California, Florida, and North Carolina from 2005 to 2008. OUTCOME MEASURES: Rate of outpatient procedures, 30-day readmissions, and hospital charges. METHODS: We performed a retrospective cohort study involving patients who underwent outpatient and inpatient lumbar discectomies and were registered in SASD and SID, respectively, for New York, California, Florida, and North Carolina from 2005 to 2008. Logistic regression models were used to demonstrate the association of socioeconomic factors with the odds of undergoing an outpatient procedure. RESULTS: Male gender (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.03-1.08), private insurance (OR, 1.93; 95% CI, 1.86-2.01), lower Charlson Comorbidity Index (OR, 4.04; 95% CI, 3.17-5.16), and higher volume hospitals (OR, 1.06; 95% CI, 1.04-1.08) were significantly associated with outpatient procedures. Higher income (OR, 0.83; 95% CI, 0.81-0.85), older age (OR, 0.996; 95% CI, 0.995-0.997), coverage by Medicaid (OR, 0.89; 95% CI, 0.83-0.96), African Americans (OR, 0.65; 95% CI, 0.60-0.70), and other minority races were associated with decreased odds of outpatient procedures. The rate of 30-day postoperative readmissions was higher among inpatients. Institutional charges were significantly lower for outpatient lumbar discectomies. The median charge for inpatient surgery was $24,273 as compared with $11,339 for the outpatient setting (p<.0001). CONCLUSIONS: Access to ambulatory lumbar discectomies appears to be more common for younger, white, male patients, with private insurance and less comorbidities, in the setting of higher volume hospitals. Further investigation is needed in the direction of mapping these disparities for appropriate resource utilization.

Outpatient follow-up of nonoperative cerebral contusion and traumatic subarachnoid hemorrhage: does repeat head CT alter clinical decision-making?

OBJECTIVES: Many neurosurgeons obtain repeat head CT at the first clinic follow-up visit for nonoperative cerebral contusion and traumatic subarachnoid hemorrhage (tSAH). The authors undertook a single-center, retrospective study to determine whether outpatient CT altered clinical decision-making. METHODS: The authors evaluated 173 consecutive adult patients admitted to their institution from April 2006 to August 2012 with an admission diagnosis of cerebral contusion or tSAH and at least 1 clinic follow-up visit with CT. Patients with epidural, subdural, aneurysmal subarachnoid, or intraventricular hemorrhage, and those who underwent craniotomy, were excluded. Patient charts were reviewed for new CT findings, new patient symptoms, and changes in treatment plan. Patients were stratified by neurological symptoms into 3 groups: 1) asymptomatic; 2) mild, nonspecific symptoms; and 3) significant symptoms. Mild, nonspecific symptoms included minor headaches, vertigo, fatigue, and mild difficulties with concentration, short-term memory, or sleep; significant symptoms included moderate to severe headaches, nausea, vomiting, focal neurological complaints, impaired consciousness, or new cognitive impairment evident on routine clinical examination. RESULTS: One hundred seventy-three patients met inclusion criteria, with initial clinic follow-up obtained within approximately 6 weeks. Of the 173 patients, 104 (60.1%) were asymptomatic, 68 patients (39.3%) had mild, nonspecific neurological symptoms, and 1 patient (1.0%) had significant neurological symptoms. Of the asymptomatic patients, 3 patients (2.9%) had new CT findings and 1 of these patients (1.0%) underwent a change in treatment plan because of these findings. This change involved an additional clinic appointment and CT to monitor a 12-mm chronic subdural hematoma that ultimately resolved without treatment. Of the patients with mild, nonspecific neurological symptoms, 6 patients (8.8%) had new CT findings and 3 of these patients (4.4%) underwent a change in treatment plan because of these findings; none of these patients required surgical intervention. The single patient with significant neurological symptoms did not have any new CT findings. CONCLUSIONS: Repeat outpatient CT of asymptomatic patients after nonoperative cerebral contusion and tSAH is very unlikely to demonstrate significant new pathology. Given the cost and radiation exposure associated with CT, imaging should be reserved for patients with significant symptoms or focal findings on neurological examination.

5-Aminolevulinic acid-induced protoporphyrin IX fluorescence in meningioma: qualitative and quantitative measurements in vivo.

BACKGROUND: The use of 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence has shown promise as a surgical adjunct for maximizing the extent of surgical resection in gliomas. To date, the clinical utility of 5-ALA in meningiomas is not fully understood, with most descriptive studies using qualitative approaches to 5-ALA-PpIX. OBJECTIVE: To assess the diagnostic performance of 5-ALA-PpIX fluorescence during surgical resection of meningioma. METHODS: ALA was administered to 15 patients with meningioma undergoing PpIX fluorescence-guided surgery at our institution. At various points during the procedure, the surgeon performed qualitative, visual assessments of fluorescence by using the surgical microscope, followed by a quantitative fluorescence measurement by using an intraoperative probe. Specimens were collected at each point for subsequent neuropathological analysis. Clustered data analysis of variance was used to ascertain a difference between groups, and receiver operating characteristic analyses were performed to assess diagnostic capabilities. RESULTS: Red-pink fluorescence was observed in 80% (12/15) of patients, with visible fluorescence generally demonstrating a strong, homogenous character. Quantitative fluorescence measured diagnostically significant PpIX concentrations (cPpIx) in both visibly and nonvisibly fluorescent tissues, with significantly higher cPpIx in both visibly fluorescent (P < .001) and tumor tissue (P = .002). Receiver operating characteristic analyses also showed diagnostic accuracies up to 90% for differentiating tumor from normal dura. CONCLUSION: ALA-induced PpIX fluorescence guidance is a potential and promising adjunct in accurately detecting neoplastic tissue during meningioma resective surgery. These results suggest a broader reach for PpIX as a biomarker for meningiomas than was previously noted in the literature.